While Obama sought to focus his remarks on Africa, European leaders were reacting angrily to a report in the magazine Der Spiegel that the U.S. National Security Agency set up electronic surveillance of European Union diplomatic missions in Washington and New York.
The report said the U.S. infiltrated computer networks and described the 28-nation bloc as a "target." The magazine cited classified documents in the possession of former NSA contractor Edward Snowden.
German Chancellor Angela Merkel's government is asking the U.S. ambassador for an explanation, her chief spokesman Steffen Siebert said at a Berlin news conference Monday. "We aren't in the Cold War anymore" and spying on diplomatic missions would be "absolutely unacceptable for us," he said.
"I'm not going to comment on any particular allegation," Obama said at the news conference. He said his national security team will evaluate the claims. Calling himself "the end user of this kind of intelligence," he said if he wants to know what the leaders of Germany, France or Britain are thinking, he phones them.
"The Europeans are some of the closest allies that we have in the world," he said.
Obama said Snowden's leaks are coming out in "dribs and drabs" and "we don't know how they're sourced."
Obama also spoke about violence in Egypt around the anniversary of Morsi's inauguration as the country's first democratically elected civilian president.
An American student, Andrew Pochter, 21, of Chevy Chase, Md., in Egypt teaching English to students, died June 28 at a demonstration in Alexandria.
An arson attack overnight by protesters at the Cairo headquarters of the Muslim Brotherhood followed earlier deadly clashes between Morsi supporters and opponents that led to eight deaths and 45 injuries, South Cairo Prosecution official Tamer El-Arabi said. At least four others were killed overnight in protests across the nation, the state-run Middle East News Agency reported.
In Dar es Salaam, thousands of people peacefully lined a two-lane highway as Obama's motorcade arrived at Tanzania's State House, where music played as the U.S. president and first lady Michelle Obama walked up a driveway temporarily renamed Barack Obama Drive with a hand-painted sign.
Tanzania is Obama's last stop on a three-nation tour of sub-Saharan Africa that also included Senegal and South Africa.
Obama has used the weeklong visit to expand U.S. investment and trade with the continent along with initiatives to increase food security and Africans' access to electric power. He also issued an executive order and $10 million commitment to expand anti-poaching efforts to protect African wildlife.
"Ultimately, the goal here is for Africa to build Africa for Africans," Obama said at the news conference. "Our job is to be a partner in that process."
"It's all tied in so that Africa is viewed as a continent not only for direct foreign investment but for trade both ways," said one of the round table participants, Jay Ireland, president and chief executive officer of GE Africa, a unit of General Electric Co., in a telephone interview. "There's a lot of consumers here. I think you're going to see real potential for U.S. exports to be a factor for Africa."
The Trade Africa initiative will initially focus on five east African countries, Burundi, Kenya, Rwanda, Tanzania and Uganda, with a combined population of 130 million people. Gross domestic product for the region quadrupled in 10 years, to more than $80 billion, the White House said in a fact sheet released before the round table.
The initiative's goal is to increase by 40 percent exports to the U.S. from the East African Community.
Before returning to Washington Tuesday, Obama will tour the Ubungo Power Plant in Tanzania to promote electric service expansion.
He'll also meet with former U.S. President George W. Bush at a wreath-laying at the U.S. Embassy in Dar es Salaam, at the memorial for victims of the 1998 embassy terrorist attack. Laura Bush is hosting a first ladies' forum in Dar es Salaam that Obama's wife will attend Tuesday.
Obama Sunday announced a $7 billion plan to boost access to electric power in the sub-Sahara and said America stands to benefit if the continent reaches its full economic potential.
General Electric is among the companies that have contributed to the $9 billion in private-sector funding for the program's first phase. It has committed to help bring 5,000 megawatts of new energy to Tanzania and Ghana.
American companies see growing opportunity in Africa. U.S. merchandise exports to the 49-country region were $21 billion in 2011, up 23 percent from 2010, according to the Office of the U.S. Trade Representative. Imports from sub-Saharan Africa were valued at $74 billion in 2011, up 14 percent from 2010. Most of that, about $60 billion, was crude oil.
With assistance from Rainer Buergin and Tony Czuczka in Berlin, Mike Cohen in Cape Town and Tarek El-Tablawy and Salma El Wardany in Cairo.